Study for transfer coefficient of iodine from grass to cow milk

Radioiodine (131I) is one of the radio nuclides likely to get released into the atmosphere in case of a reactor accident, though chances of such an accident are very remote due to stringent engineering safety features. During the short initial phase of accidental release of radioactivity, 131I is transferred through grass-cow milk pathway, leading to significant thyroid dose to those consuming milk, especially infant and children. Transfer coefficients are important for quick evaluation of environmental contamination, during both normal and abnormal operational phases of a nuclear facility. Transfer coefficient of iodine from grass to milk is defined as ratio of iodine concentration in milk (Bq.L-1) obtained at equilibrium for a constant rate of intake of iodine in (Bq.D-1). During normal operation conditions of nuclear power reactor, the release of radioactive iodine isotopes is are too low that they are not present in measurable concentrations in the environment. Hence, studies are to be performed using stable iodine to estimate the transfer coefficient. A method has been developed based on thermal neutron activation analysis (NAA) to estimate the stable iodine concentration present in grass and cow milk. The method involves pre-concentration from matrix, neutron activation and gamma spectrometry and these were standardized